1. Field of the Invention
The present invention relates to a light emitting diode package, and more particularly, to a side-view type light emitting diode package adopting an opening portion, wherein at least a portion of an inner wall of the opening portion is provided with a step projection.
2. Discussion of the Background
Generally, a light source system using a light emitting diode chip is formed by mounting a light emitting diode chip into various kinds of packages depending on their use. Since a side-view type light emitting diode package is located on a side surface of a light guide plate to provide light in parallel therewith, it is generally used as a backlight illuminator for a display.
FIGS. 1 and 2 are plan and perspective views illustrating a conventional side-view type light emitting diode package, respectively, and FIG. 3 is a sectional view taken along a dashed dotted line A-A of FIG. 1.
Referring to FIGS. 1 to 3, the side-view type light emitting diode package includes a pair of lead terminals, i.e., first and second lead terminals 11 and 13. The first and second lead terminals 11 and 13 are formed out of a lead frame manufactured with a phosphor bronze plate, and a surface thereof is plated with silver in order to increase light reflectivity. The first and second lead terminals 11 and 13 are supported by a package body 15. The package body 15 is generally formed by insert molding the lead terminals with polyphthalamide (PPA).
For convenience of description, the package body 15 may be sectionalized into an upper package body 15a and a lower package body 15b based on the position level of the first and second lead terminals 11 and 13.
The upper package body 15a has an opening portion 16 for exposing the first and second lead terminals 11 and 13. The first and second lead terminals 11 and 13 are positioned on a bottom surface of the opening portion 16, i.e., on the lower package body 15b, and spaced apart from each other in the opening portion 16. Further, the first and second lead terminals 11 and 13 protrude to the outside of the package body 15 in order to be electrically connected to an external power source. The first and second lead terminals 11 and 13 which protrude outward may have various shapes and be bent with various shapes. FIGS. 1 and 2 show the first and second lead terminals 11 and 13 which are bent from a lower surface of the package body 15 to side surfaces thereof to implement surface mounting.
A light emitting diode chip 17 is mounted onto the first lead terminal 11 in the opening portion 16 to be electrically connected to the first lead terminal 11, and electrically connected to the second lead terminal 12 using a bonding wire 19. The opening portion 16 may be filled with a light-transmittable resin 23, and a phosphor may be contained in the light-transmittable resin.
The conventional side-view type light emitting diode package is provided with the opening portion 16 with an elongated shape, and sidewalls, specifically sidewalls 15w in a major axis are formed to be inclined to widen a visible angle in the major axis. Accordingly, a side-view type light emitting diode package suitable to a backlight for display may be provided, and a side-view type light emitting diode which emits white light may be provided by the suitable selection of a light emitting diode chip and a phosphor.
However, in the conventional side-view type light emitting diode package, when the opening portion 16 for exposing the light emitting diode chip is filled with the light-transmittable resin 23 containing a phosphor, the light efficiency may be reduced since an upper surface of the light-transmittable resin 23 is formed to be concave. If the amount of the light-transmittable resin 23 increases to solve such a problem, the light-transmittable resin 23 may protrude above an upper surface of the package body 15, so that the light-transmittable resin 23 may be damaged by external force.